Elevator door



E. W. FENN.

ELEVATOR DOOR.

APPLICATlON men 050.13, 1919.

J; ATTORNEY.

Patented Aug. 1, 1922.

Fig.3

V. c a 2 v Wzv fi o, //r W m .a H 1 if w k Li i 1 Q 1 1 1 I i I I I I I l I I I I I 1 I .1

EMORY W FENN, 01F o, rainers, Assrenon T0 trial: rnnL E COMPANY, or

BROOKLYN, rvnwronn, A conronlirronornnw ronic.

ELEVATOR DOOR.

Specification of Letters l ifatent.

Eatented Aug. 1, 1922.

Application fi1ed December 13, 1919. Serial No. 344,724.

To all whom it may concern:

Be it known that l, EMORY W. PENN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in ElevatorDoors, of which the following is a specification, reference being had therein to the accompanying drawings, which form apart thereof. My invention relates to elevator doors, and more particularly to a door of this character known as a pass type'd'oor wherein the door openings of adjacent floors are each closed by a door composed of two sections, oppositely movable in parallel vertical planes, the upper section otone door be ng spaced away from the wall of the shaft to afford clearance for the lower section of the other door, thus permitting the adjacent sections to pass each other when opening or closing either of said doors.

llleretofore in this art doors of the pass type have had the two sections mounted upon parallel straight tracks, the upper section of each door being spaced away from the wall of the elevator shaft suliiciently to permit the passage of the lower section of the door above between it and'the door opening, or to permit the upper section 'oii'one door to pass the lower section of: the closed door above it on the shai't'side thereof.

flu the type of door to which I have above reilerred, a pivotal shield is used to close the gap between the upper door section and the wall of the shaft when any door is closed. This construction. howeveiyis not desirable, as it does not secure a sufficiently tight closure of the door opening to guard against passage of smoke and flames in the event of lire, andiloes not afford sutficiently rigid locking means when the doors are closed to prevent displacement of the doors under the tm-ee ot' blows thereon Furthermore, it requires a double guide rail structure throughout the slia'tt.

The pass type of door is employed where the clearance between the lintel of one door and the sill ot the door immediately above is not sufficiently great to permit the use of doors, the sections o'f which have movement in the same vertical plane, known as regular type doors, Conditions are sometimes such that it'is' 'essentialto use the pass type of door throughout an entire shaft, and sometimes such that this type of door may be used at some openings and the regular type doors at other openings.

My present invention has to do with an elevator door structure wherein each or two adjacent doors'has one section of thepass type and the other section of the regular type, thus permittingthe application of a pass type door embodying my invention to one particular floor of abuilding wherein the clearance between door-openings is not sufiicient to permit the use of a regular type of door at that particular floor. A door made in accordance with my present invention employs a single guide rail at each side of the door, which is so formed that one of the door sections, when opening and ClOSlllg the door, will have a directly vertical movement, while the other section will have a combined vertical andhorizontal movement, the two door sections, when the door is closed, beir g brought into the same vertical. plane;

It is essential that the lower section of one door and the upper section oi"? the adjacent door be so constructed and mounted that either Willpass the other as a result of the combined horizontal and vertical movement above referred to.

Upon the wall rail which carries the guide rail, I provide suitable guides co-operating with a supplemental shoe upon the pass type door section, which will ensure a horizontal parallel movement of the door during its vertical travel, and I associate therewith what may be termed an automatic switch mechanism which will ensure a return paral el movement upon the closing of the door. This switch mechanism also acts as a binder to hold the door section against horizontal displacement adjacent the sill and the lintel thereof, when the doors are in the closed position.

The two sections of a door are connected by a chain, cable or other flexible connection, so as to ensure their simultaneous movement in opposite directions,'it being essential to so arrange the pulley over which 'this'conmost remote from the wall of the shaft,

through which a special guide shoe pass so as to provide suitable guides adjacent the'top and bottom door sections when the special guide passes out of the operative range of the guide member carried by the wall rail.

I also utilize said guide member co-operating with the pass type upper section of a Cl001, aS a positive stop to prevent the falling of this section in the event of breakage of the flexible connection.

U The invention consists primarily in an elevator door embodying therein two door sections, one of which when opening and closing has a vertical movement only, and the other of Which has a vertical movement and a horizontal component of movement, and a single guide rail for both of said sections; and in such other novel features of construction and combination of parts as are hereinafter set. forth and described, and more particularly pointed out in the claims hereto appended.

I Referring to the drawings,

Fig. '1 is a vertical section of a portion of an elevator shaft embracing two door openings and a door structure at each opening, both doors being closed,

-Fig. 2 is a similar view with the lower door open; it

Fig. 3 is a detail view upon a larger scale of the door structure at the upper openings shown in Figs. 1 and 2, With-the door in the closed position Fig. 4 is a plan view of Fig. 2 upon an exit larged scale, and

Fig. 5 is a detail perspective view of one upper corner of the upper section of. the lower door in Figs. 1 and 2, showing the relation of the upperguide shoe upon said section, and the guide carried by the wall rail. 1

Like letters refer to like the several views.

Since the arrangement of the guide rail and its associated guides and switches, and the construction at each side of the door, is

parts throughout duplicated upon opposite sides of the door opening, and of the door sections, a detailed showing of but one side of the door strucis shown at A, and the lower door opening at B. The lintel line of the door A is in dicated at a and the sill line ate, and the lintel lin of the door B. is shown at b and the sill line at Z).

Within the shaft. on each side of the door opening is a vertically extending. wall rail 0 extending throughout the shaft upon opposite sides of the several door openings. This rail differs from the ordinary angle rail now ordinarily employed, merely in the respect that the inwardly extending flange thereof adjacent the lower half of the door opening A, and the upper half of the door opening B is wider than other portions thereof, as shown at c.

Mounted upon each wall rail is a guide rail having two parallel vertical sections cZ-6Z connected by oblique sections d the section cl, extending from adjacent the lower part of the dooropening A to adjacent the upper part of the opening B, being more remote from the wall of the shaft than the section d, and the sections 6Z2 connecting said sections (Z and d. This guide rail structure therefore presents the characteristic of a single rail having two sections extending in parallel vertical planes connected by oblique sections, the purpose of which will i more fully. appear hereinafter.

The door opening A is closed by means of a door comprising an upper door section 6 provided with the ordinary guide shoes ee adjacent the top and bottom thereof respectively, and co-operating with the section (5 of the guide railupon which it has vertical movement in one plane only; and a lower section f mounted. to have movement upon the sections (Z (Z and d of said rail by means of upper guide shoes 7, a lower guide shoe f and a supplemental guide shoe f intermediate said shoes, so as to have a combined vertical and horizontal movement. The section 7, when the door is closed, occupies the same plane as the vsection 6, but

a plane parallel therewith and spaced away therefrom sufficiently to pass the upper sectron of the door closing the opening B when the door is open.

Mounted upon the portion 0 of the wall rail 0 and adjacent the sill a, is a fixed guide member 9 having an inclined face presented inwardly and upwardly of the shaft, said guide member being located in the path of movement of the shoe so as to co-operate with the section 45 and the shoes f when impag'ting the desired horizontal component of movement to the door section 7". Also carried by the rail c and cooperating with the shoe is a pivotal guide or switch member It mounted adjacent the guide 9, the purpose of which is to hold the lower door section 7 closely adjacent the wall of the shaft when the door is m the closed posltlon, serve as a guide for the shoe f ras es??- when closing the door to ensure its following the guide 9: during this action.

The shoe is of a length so that when passing between the fixed guide member 9 and movable guide or switch it, it will remain in a vertical position and thus avoid any substantial tilting action of the door. The upper part of the pivotal guide or switch member h is overweighted so as to be normally out of poise, the two arms of said switch mechanism being oi a length, and the end so formed, that when the door is open, the upper end will bear against the wall flange of the wall rail 6', and the lower end will bear against the guide rail (Z so as to hold this member in a position where the horizontal movement of the door, in closing, will be assured and possible displacement of the member and a resultant jamming of the door will be avoided.

The two door sections 6 and f' are con nected by a flexible cord or strand 2' passing over the sheave 2" carried by a fitting adja cent the lintel oi the door opening 1. The connection 2' is seemed to an offset fitting 6 adjacent the bottom the door section 6, and the other end thereof is connected to an offset fitting f adjacent the top of the lower section Carried by the side rail 0 is a stud h against which the shoe i forces said guide inelnberlz, as the door comes to the closed position, all stresses upon the door being transferred to said stud through said pivotal guide or switch member 71..

To secure the desired clearance for the shoe f this shoe is offset from the bottom of the section 7- so as to be normally positioned below the guide member 9, and thus avoid interli'erence therewith.

Since when the lower door section 7' is of the pass type, it will. when the door is open,

be spaced away from the sill oil the door opening by slightly more than the thickness of a door section, i provide the top 01 said section with a truck bar of sufficient width to project from said section when it is in the fully open position, across the space be tween it and the sill of the door, and thus avoid the presence of a gap into which the wheels oi" trucks might drop when passing to and :lrom an elevator car. The section 6 is provided with an offset astragal e' adapted to receive the offset truck bar Since a door is seldom more than two inches in th'ckncss, said truck bar and said astragal will not seriously interfere with conditions about a door, even though, when a door is closed, they project within the door opening,

The door closing the opening is composed of an upper section mounted upon the sections a, d" and (Z of the guide track so 7 as to have simultaneous vertical and horizontal movement, and the lower section is mounted upon the section d of said track.

The section like the section is Jrovided a v with shoes j constantly engaging the track,

which shoes correspond with the shoes f upon the section f of the door immediately above the section 7'. Said section is also provided with an offset guide shoe j similar the shoe f upon the section j, and a supplemental guide slice j corresponding in function with the shoe The section it: is provided with guide shoes is and A? corresponding itn the shoes 6 and 6- upon the section 6 ol the door heretotore described.

harried by the wall rail 0 is a guide memher 772 corresponding with the guide member g, but differing therefrom in that its position is inverted, since it must cooperate with an upwardly moving door instead of a downwardly moving door. The member We is provided with a bridge we. adapted to be engaged by the shoe 7' when the door closing the opening B is in the closed position, thus preventing the falling of the section j in the event of breakage of the cables connec ting it and the section k.

Mounted adjacent the guide member on is a pivotal guide member or switch )lwhich is overweighed so as to have a normal tend ency to drop away from the guide member 722., said member it having a heel or adapted to engage a stud it carried by the wall rail 0, so that any stresses applied to this section from the floor side of the opening will be transmitted through the shoe and said heel n to said stud, and thus prevent displace--- ment of the door.

lVhen the upper door section only has vertical and horizontal movement, the truck bar and astragal construction heretofore de scribed cannot be used, so that such doors may be equipped with the ordinary astragal, the top of the lower section itself servin as the truck bar and not requiring any oiisetting thereoi in the manner heretofore described. The manner of connecting the two doors as described above, the sheave i of each door structure having its axis parallel with the wall of the shaft adjacent the door opening so as to compensate for the hori' zontal componentof movement of one ofthe door sections whenever the pass type construction heretofore described, is used.

lit will be observed that in both the upper door structure and the lower door. structure shown in Figs. 1 and the door section of tion the various parts that when the door has closed attained its maximum horizontal movement,

" structure is substantially is follows In F 1 ot the drawings, the doors at the openings A. and B are both shown as being closed, while in Fig. 2 the door at the opening B is shown as being opened. In desdribing the operation, I will first refer to what occurs when door at the opening B is opened. and closed, and then give a similar description of the action of the door A under the same conditions.

By reference to Fig. 1, it will be observed that the guide rail section (Z adjacent each door opening, when the doors are closed, will h old the door section having directly vertical movement thereon, in close juxtaposition to the wall of the shalt, and that the other section of each door, such section being oil the pass type, will have that edge thereof adjacent the middle of the door opening, held in close juxtaposition to the Wall of the shaft by said section (Z, and the opposite edge thereof similarly held by the movable guide or switch member cooperating with that door, the stud acting upon said guide or switch member limiting the oscillatory movement thereof under the control of the door and transmitting any strains upon the door to the wall rail 0+0.

The truckable feature of the door so tar as the stopmechanism carried by the guide rail is concerned, is old'and well known in the art and has therefore notbeen shown nor described. This is also true of the controlling mechanisms for the doors, since in these respects the door may be of the manually operative, semi-automatic or full automatic type.

In opening the door closing the opening B, the lower section 70 will have a directly vertical tall, being guided in its movement by the portion of the rail section (Z co'-operating with the shoes 70 and 70?. With the initial movement of the upper section y' of this door, the shoe y" willpass from the section (Z ontothe oblique section (Z the supplemental guide shoe 7' by its engagement with the fixed guide member m, the contact surface of which substantially parallel with that of the section (Z causing said'section y immediately after its initial movement, to

have an upward vertical movement with a horizontal component of movement as determined by the angle of the contact surface of the guide m and of the oblique rail section diately d l l ith the upward movement of the shoe j", the engagement oi the lower end thereof witli the movable guide member or switch a will impart a movement thereto sutlicient to term clearance space equal to the length of the shoe between it and the fixed guide m, one end of this shoe being guided by the ember m and the other end thereof by the member a. Hence there will be no tilting of either the door section or oil? the shoe jithe door section at all times occupying a sub stai'itially vertical position.

As the section 7' begins to rise, the-offset shoe j carried thereby will leave the bridge m of the guide or and will pass in an oblique course toward the opening 0 in the 1 section 0. Substantially simultaneously with the passage of the shoe j from the sec-- tion (Z of the guide rail, the shoe 7' Willbe brought into a position where it will straddle the railsection (5 beyond said gapc and thus co-operate with the shoe 7" in guiding the door section its fur her movement. The supplemental shoe j", substantially simultaneously with the engagement of the shoe with the rail section cl, will pass from its operative relation to the guide members .-a, having no further function during the opening movement oi the door.

By reason ot the over-weighting of the guide member a, it will remain in an overbalanced position with the upper end thereengaging the rail section cl and the lower end thereof engaging the wall flange of the wall rail 0, thus so positioning said guide or switch member a that it will receive the sup pleinental shoe j during the closing move thesame parts cO-oPeiating in the manner above reterredto, to guide the section j in its oblique travel "toward its position in close juxtaposition to the wall of the shaft adjacent the door opening B. i

in opening the door, the movement thereof inwardly of the shaft will be su'liicient to cause the section y to pass about the guide meniberg adjacent the sill oi the door immeabovc, and past the lower doo'r section at the door opening A. The extent of the pass movement of the pass type door section is immaterial, it being possible to use a door of this type where the clearance be tween the lintel of one door opening and the sill oi the door opening immediately above, is from fifteen to eigl'iteen inches.

7 It is to l e observed that with a pass type door structure made in accordance with my invention, it is essential'that the doors at two adjacent door openings each be so constructed that the adjacent sections of the the doors at other openings, of the regular type. Hence my invention contemplates the use of two door ;tructi;u'es, one co-o ierating with the other. which cor. ..ucti0n is essential, because when the doors are rinsed they occupy the same vertical plane, and hence while the horizontal component of motion is necessary to secure the clearance "for the opening of one door, it is equally true that the same conditions exist as to the adjacent door. I

i idverting to the operation of the door closing the opening 3., will be as heretofore described in connection with. the door at the opening B, with the exception that the upper door section 6 will have only a vertical movement, while the lower door section 7 will have a vertical movement with a horizontal component under the control of the fixed guide member 9, the movable guide or switch member h, the upper portion of the guide rail section (Z, the upper portion of the offset guide rail section (Z, and the oblique connecting guide rail. section (Z As the section f of this door comes to rest, the truck bar f will span the gap between this section and the door sill a, the astragal 6 coming to rest adjacent. but be low, the lintel a. When the door is closed, said truck bar and said astragal will project within the door opening, but the extent of this projection will not be sufficient to obstruct the space within the door opening.

By using a sheave 2" having its axis parallel with the wall of the shaft adjacent the door opening, one reach of the connecting strand or cable i will be positioned in substantial vertical alinement with the bracket 6 upon the door 0, while the other reach will have perfect freedom of movement toward and from the rail 0 without interfering therewith, since the offset bracket f will project across the edge of the wall rail 0 and will be caused to follow same by the movement of the door section carrying said bracket. The horizontal movement of the door is so small that this change of position of one reach of the connection between the door sections will have no appreciable elfect upon the functioning of the door.

The importance of the arrangement of the sheave 11 as described results from the fact that if the axis of the sheave were otherwise arranged, said connection would have a tendency to constantly ride upon the edge of the sheave, and thus present a constant likelihood of the falling of the doors.

As the upper section of the door closing the opening- B and the'lower section of the door closing the opening A come to the fully closed position, the supplemental shoe carried thereby respectively will restore the movable guide or. switch member to its normal position where it willbe removed from adjacent the guid rail section (5, thus affording clearance for the passage of the (Jo-operating door section of the pass type. The shoe 7' or 7' will come to rest engaging one arm of its co-operating movable guide or switch member h or n, respectively. and forcing it into engagement with its stop stud h or n with the result that this switch member and its co-operating stud in each instance will serve as a binder to hold the door firmly against the wall of a shaft.

It is not intention. in the present application, to claim broadly an elevator door of the pass type in which a door section or sections have a vertical movement with a horizontal component in opening and closin same, so that the section or sections of one door may pass the section or sections of adjacent doors while being in the same vertical plane when in the closed position. The present invention is limited to an elevator door in which one section only is of the pass type, the other section being of the regular type. I

The accompanying drawings are largely diagrammatic, since it is impossible to show the invention clearly with a drawing to scale. Many characteristics of doorsof this type which are well known in the art are neither shown nor described, such being immaterial to the present invention.

It is not my intention therefor, to limit the invention to the precise details of construction shown in the accompanying drawings. it being apparent that such may be varied without departing from the spirit and scope of the invention.

Having described the invention, what I claim as new and desire to have protected by Letters Patent. is j 1. An elevator door embodying; therein tw door sections. one of which when openinn" and closing; has a vertical movement only, and the other of which has a vertical. movement and a horizontal component of movement, and a single guide rail for both of said sections.

2. An elevator door embodying therein a single guide rail having: two sections occupying parallel vertical. planes, and a connecting oblique section adjacent each side of a door opening, a door section mounted to have movement upon the vertical section of said rail nearer the door opening, a second door section adapted to have movement upon said last named vertical, said oblique, and said. other vertical rail sections, and an inclined guide member operative upon said second door section.

3. An elevator door embodying therein a single guide rail having two sections .00 cupying parallel vertical planes, and a connecting oblique section adjacent each side of a door opening, a door section mounted to have movement upon the vertical section of said rail nearer the door opening, a second doorsection adapted to have movementupon said last named vertical, said oblique, and said other vertical rail sections, an inclined guide member, the operative surface of which is substantially parallel. with that of said oblique rail section, a second guide member pivotally mounted adjacent, and having an operative surface adapted to be positioned parallel with but spaced away from the operative surface of said inclined guide member, and a guide shoe carried by said last named door section adapted to operatively engage both of said guide members.

4. An elevator door embodying therein a single guide rail having two sections occupying parallel vertical planes, and a connecting oblique section adjacent'each side of a door opening, a door section mounted to have movement upon the vertical section of said rail nearer the door opening, a second door section adapted to have movement upon said last named vertical, said oblique, and said other vertical rail sect-ions, an inclined guide member, the operative surface of which is substantially parallel with that I of said oblique rail section, a second guide member pivotally mounted adjacent, and having anoperative surface adapted to be positioned parallel with but spaced away from the operative surface of said inclined guide member, and a guide shoe carried by saidlast'named door section adapted to operatively engage both of said guide members, said movable guide member being so positioned as to be engaged by said guide shoe when the door is in the closed position, and a stud adapted to be engaged by said movable guide member, whereby movement of said door section carrying said guide shoe away from the wall ofthe shaft, is prevented when the door is in the closed position.

5. An elevator door embodying therein a single guide rail having two sections occupying parallel vertical planes, and a connecting oblique section adjacent each side of a door opening, a door section mounted to have movement upon the vertical section of said rail nearer the door opening, a second door section adapted to have movement .upon said last named vertical, said oblique,

and said other vertical rail sections, and an inclined guide member operative upon said second door section, said rail section more remote from the wall of the shaft having a gap therein, and said second door section having a shoe offset with relation to one horizontal edge thereof adapted to pass through said gap, and to be automatically engaged with and disengaged from the guide rail adjacent said with the opening and the closing of the door.

6. Anelevatordoor embodying therein a slngle' guide rail having two sections occupying parallel vertical planes, and a connecting oblique section adjacent each side of a oor opening, the guide rail section nearer the wall of the shaft extending adjacent the upper half of the door opening,;

and said oblique and said other vertical sections extending adjacent the lower part of said opening, an upper door section having guide shoes co-operating with the guide rail section nearer the wall of the shaft, a lower door section having guide shoes co-operating with said last named vertical, said oblique and said other vertical rail sections, an inclined guide member operative upon said lower door section, an offset truck bar carried by said lower door section, whereby when the door is open, said truck bar will span the gap between its door section and the sill of the door opening, and an offset astragal carried by said upper door section and adapted to inclose the edge of said truck bar when the door is closed, said truck bar and. said astragal being. projected within the door opening when the door is closed.

7. An. elevator door embodying therein a single guide rail having two sections occupying parallel vertical planes, and a con necting oblique section adjacent each side and said oblique and said other vertical sec-' tions extending adjacent the lower part of said opening, said last named 'verticalsection having a gap therein, an upper door section having guide shoes co-operating with the guide rail section nearer the wall. of the shaft, a lower door section having guide shoes co-operat-ing with'said last named vertical, said oblique and said other vertical rail sections, an offset shoe carried at the lower edge of said lower door section adapted'to pass through said gap and to be automatically engaged with and disengaged from the guide rail adjacent said gap with the opening and the closingof' the door, an inclined guide member operative upon said lower door section, an offset truck bar carried by said lower door section, whereby when the door is open, said truck bar will span the gap between its door section and the sill of the door opening, and an oifset astragal carried by said upper door section and adapted to inclose the edge of saidtruck bar when the door is closed, said truck bar and said astragal being projected within the door opening when the door is closed;-

8. An elevator door embodying therein with the wall of the shaft adjacent said door opening, and a flexible connection passing about said sheave and having its opposite ends connected with said door sections re spectively.

9, in levator door embodying therein a single guide rail having two sections occupying pa *allel vertical planes, and a connectingoblique section adjacent each side ol? a door opening, a door section mounted to have movement upon the vertical. section of said rail nearer the door opening, a secend door section adapted to have movement upon said last named vertical, said oblique, and said other vertical rail sections, an inclined guide member operative upon said second door section, said guide rail being carried by an angular wall rail, the inwardly projecting flange of which extended adjacent said oblique rail section and said rail section more remote from the wall of the 'hatt, an olliset bracket carriedv by each of i l door sections and extending across the edge of said wall rail, a sheave adjacent the lintel oi? the door opening and having its axis parallel with the wall. of the shatt adjacent said opening, and a flexible con nection passing about said sheave and hav ing; its opposite ends connected with said brackets respectively.

10. An elevator door structure embodying; therein doors closing adjacent openings in a shaft, the door at the upper opening comprising an upper section having a vertical movement only, and a lower section having a vertical. movement with a horizon tal con'iponcnt, and the door at the lower door opening; comprising a lower section having; a. vertical movement only, and the upper section. having; a vertical movement ith a lmrizontal component, and guiding meal 'or said door sections respectively.

ll. In an elevator door structure. the c0mll i l;.nation oil a ,euide rail having alined vert cal sections one adjacent the upper part cl one door opening, and. the other adjacent the lower part oi the door opening immediately below, a vertical section parallel with and arranged intermediate said other vertical sections, and positioned more remote from the wall of the shaft, and oblique sect ons connectinp' said last named and said first named vertical sections, an inclined ,Q'uide adjacent the sill of the upper door opening having an operative surface substantially parallel with the oblique rail section adjacent that door opening, an inclined guide adjacent the lintel of the lower door opening having an operative surtace sub stantially parallel. with the oblique rail section adjacent that door opening, doors closing said door o iieningrs respectively, the door losing the upper door opening comprising an upper section having movement upon the rail section nearer the door opening, and

the lower door section having movement upon said last named railsectiornthe vertical tion parallel therewith and the connectoblique section, a guide carried by said door section cooperating with the ,g, ,ide member adjacent the sill of that door opening, and the door at the lower door opening comprises a door section having movement on the guide rail section adjacent the sill of said lower door opening, and an upper door section adapted to have movement upon said last named vertical rail section, said other vertical section adjacent the lintel of said lower door opening, and the connecting oblique rail section, and a guide shoe carried by said last named upper door section cO-o wrating with the inclined guide adjacent the lintel of the lower door opening.

12. ln an elevator door structure, the combination of a guide rail. having alined vertical sections one adjacent the upper part of one door opening, and the other adjacent the ower part of the door opening immediately below, a vertical section parallel with and arranged intermediate said other vertical sections, and positioned more remote from the wall of" the shaft, and oblique sections connecting said last named and said first named vertical sections, said last named vertical rail section having a gap therein, an inclined guide adjacent the sill of the upper door opening having an operative sur face substantially parallel with the oblique rail section adjacent that door opening, an inclined guide adjacent the lintel of the lower door opening having an operative surface substantially parallel with the oblique rail section adjacent that door opening doors closing said door openings respectively, the door closing the upper door opening comprising an upper section having movement upon the rail section nearer the door opening, and the lower door section ha vino movement upon said last named rail section, the vertical section parallel therewith and the connecting oblique section, a guide carried by said lower door section coo ieratino; with the guide member adjacent the sill of that door opening, and the door at the lower door opening comprises a door section having movement on the guide rail section adjacent the sill of said lower door opening, and an upper door section adapted to have movement upon said last named vertical rail section, said other vertical section adjacent the lintel 01 said lower door open ing. and the connecting oblique rail section, and a. guide shoe carried by said last named upper door section co-operatingwith the inclined guide adjacent the lintel of the lower door opening. the lower door section at the upper door opening having a guide shoe offfrom the lower edge thereof, and said upper door section closing the lower door opening having at the upper edge thereof:

an ofiset guide shoe, said offset guide shoes my signature, in the presence of two subrespectively being adapted to pass through scribing witnesses, this 3rd day of Decemsaid gap and be automatically engaged with her 1919.

or disengaged from she guide mil, with the EMORY W. F ENN. opening and theclosing of said doors re- Witnesses: speetively. F. T. WENTWORTH,

' In Witness whereof I have hereunt o affixed E. BENTON. 

